Methods and materials for determining the efficacy of prostate cancer therapies

ABSTRACT

Methods for monitoring, and determining the efficacy of, a treatment for prostate cancer in a subject are provided, such methods including detecting the levels of expression of multiple polypeptide biomarkers in biological samples obtained from the subject prior to, and during, a course of treatment. Specific patterns of changes in the expression of the polypeptide biomarkers are indicative of the effectiveness of the treatment in the subject.

REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.13/600,048, filed Aug. 30, 2012, which is a continuation-in-part of U.S.patent application Ser. No. 13/291,994, filed Nov. 8, 2011, thedisclosures of which are hereby incorporated by reference.

REFERENCE TO SEQUENCE LISTING

This application incorporates by reference in its entirety the SequenceListing contained in the accompanying file, named “1005div_seqlist.txt,”the size of which is 51 KB, and which was created on Dec. 9, 2013.

TECHNICAL FIELD

The present disclosure relates to methods and compositions fordetermining and monitoring the efficacy of therapeutic interventionsemployed in the treatment of prostate cancer.

BACKGROUND

In many countries prostate cancer is the most common, or the second mostcommon, cancer diagnosed in males. Unless detected early, prostatecancer may spread to the spine and bones of the patient, causing severepain, bone frailty and death. Between 20 and 30,000 men die each year inthe United States, 600 in New Zealand and 2000 in Australia, fromprostate cancer. The use of prostate specific antigen (PSA) as adiagnostic biomarker for prostate cancer was approved by the US FederalDrug Agency in 1994. In the nearly two decades since this approval, thePSA test has remained the primary tool for use in prostate cancerdiagnosis, in monitoring for recurrence of prostate cancer, and infollowing the efficacy of treatments. However the PSA test has multipleshortcomings and, despite its widespread use, has resulted in only smallchanges in the death rate from advanced prostate cancers. To reduce thedeath rate and the negative impacts on quality of life caused byprostate cancer, new tools are required for more accurate primarydiagnosis, for assessing the risk of spread of primary prostate cancers,and for monitoring responses to therapeutic interventions.

The PSA blood test is not used in isolation when checking for prostatecancer; a digital rectal examination (DRE) is usually also performed. Ifthe results of the PSA test or the DRE are abnormal, a biopsy isgenerally performed in which small samples of tissue are removed fromthe prostate and examined. If the results are positive for prostatecancer, further tests may be needed to determine the stage ofprogression of the cancer, such as a bone scan, a computed tomography(CT) scan or a pelvic lymph node dissection.

Currently, the established prognostic factors of histological grade andcancer stage from biopsy results, and prostate-specific antigen level inblood at diagnosis are insufficient to separate prostate cancer patientswho are at high risk for cancer progression and require aggressivetreatment, from those who are likely to die of another cause.

An important clinical question is how aggressively to treat patientswith localized prostate cancer. Treatment options for more aggressivecancers are invasive and include radical prostatectomy and/or radiationtherapy. Androgen-depletion therapy, for example usinggonadotropin-releasing hormone agonists (e.g., leuprolide, goserelin,etc.), is designed to reduce the amount of testosterone that enters theprostate gland and is used in patients with metastatic disease, somepatients who have a rising PSA and choose not to have surgery orradiation, and some patients with a rising PSA after surgery orradiation. Treatment options usually depend on the stage of the prostatecancer. Men with a 10-year life expectancy or less, who have a lowGleason score from a biopsy and whose cancer has not spread beyond theprostate are often not treated. Younger men with a low Gleason score anda prostate-restricted cancer may enter a phase of “watchful waiting” inwhich treatment is withheld until signs of progression are identified.However, these prognostic indicators do not accurately predict clinicaloutcome for individual patients.

One feature of prostate cancer is that the phenotype of the diseasevaries from one patient to another. This is the major problemconfronting the physician who seeks to develop the best treatmentprotocol for each patient. Prostate cancer in different individualsdisplays very heterogeneous cellular morphologies, growth rates,responsiveness to androgen and its pharmacological blocking agents, andmetastatic potential. This heterogeneity in cancer phenotype isreflected in the treatment regimes used by physicians in that differentprostate cancer phenotypes are responsive to very different drugregimes.

Treatment options for patients with metastatic prostate cancer arelimited in their effectiveness. After development of resistance toandrogen-depletion therapy, a patient may proceed to second-linehormonal therapy with ketoconazole, estrogen and Leukine™, and then todocetaxel chemotherapy (Tannock et al., N Engl J. Med.2004;351:1502-1512; de Bono et al., N Engl J. Med. 2011;364:1995-2005;de Bono et al., Lancet. 2010; 376:1147-1154; Kantoff et al., N Engl J.Med. 2010;363:411-422). After ketoconazole and docetaxel, the treatmentoptions left for metastatic prostate cancer patients are three furtherdrugs with FDA approval, namely Jevtana™ (cabazitaxel), Provenge™(Sipuleucel-T) and Zytiga™ (abiraterone), but all are associated withmedian survivals of less than 2 years. In part, the impact on survivalis the result of low response rates, indicating a significant proportionof patients exhibiting de novo resistance to these agents. Other drugsused in the treatment of other cancers, such as Sprycel™, show promisein use against prostate cancer. After the use of FDA-approved drugs,there is a fairly long list of drugs where phase II results suggestpossible clinical utility against prostate cancer, includingNovantrone™, 5-fluorouracil, doxorubicin, platinum-based drugs,methotrexate and etoposide. However, there is been no reliable way toidentify which of these drugs might have the greatest chance at successin treating specific patients.

For each drug application, routine follow-up laboratory tests are usedto monitor the health of the patient. These include haemoglobin levels,blood cell count, platelet count, creatinine levels, liver enzymes,alkaline phosphatase and bilirubin. Different patients responddifferently to chemotherapy and response rates are low. This is due tothe patient's phenotype as revealed by the spectrum of side-effectscaused by differences in drug metabolism and pharmacokinetics,polymorphism of detoxification enzymes leading to drug toxicity, and ageneral suppression of innate and adaptive immunity.

For prostate cancer patients, a major issue is that the androgenreceptor numbers in cells increase in many prostate cancers afterchemotherapy (Culig et al., J Cell Biochem. 2006; 99:373-381). This iswhy new drugs, such as Zytiga™ and now Enzalutamide (MDV3100) have beendeveloped to try and circumvent the role of the receptors. Somemetastatic and primary prostate cancers retain activation of theandrogen receptor in processes that are entirely independent of theandrogen ligand. There are a number of mechanisms for this, includingup-regulation of androgen receptor expression through amplification ofthe androgen receptor gene (Visakorpi et al., Nat Genet 1995; 9:401;Chen et al., Nat Med 2004; 10:33; Edwards et al., Br J Cancer 2003;89:552), increased sensitivity of androgen receptor via overexpressionof nuclear co-activators (Gregory et al., Cancer Res 2001; 61:2892.),and splice variant mutations of the receptor (Watson et al., Proc NatlAcad Sci USA 2010; 107:16759; Guo et al., Cancer Res 2009; 69:2305).

While there is a report of the molecular profiling of patients showingoverexpression of the androgen receptor after a failed response todocetaxel, and then a dramatic response of measurable disease tosecond-line hormonal therapy with ketoconazole, estrogen and Leukine™(Myers et al., Case Rep Oncol. 2012 January-April; 5(1): 154-158),little has been done to try and evaluate why patients fail chemotherapy.

There are currently no effective tests to monitor whether or not apatient is responding to a particular therapy, such as administration ofone or more chemotherapeutic agents. The ability to monitor theeffectiveness of an on-going treatment regime in a patient would enablea clinician to determine whether the patient should remain on thatregime or should be put on a different treatment regime. There thusremains a need in the art for an accurate test for monitoring theefficacy of treatment regimes in subjects with prostate cancer.

SUMMARY

The present invention provides a minimally invasive test that can beemployed to monitor the efficacy of treatment regimes in prostate cancerpatients, together with materials for performing the test. The disclosedmethods detect multiple biomarkers and correlate their expression levelswith the progression or regression of prostate cancer in a subject. Incertain embodiments, the methods utilize patterns of expression ofbiomarkers to distinguish between subjects who are responding to aparticular prostate cancer treatment regime and those who are notresponding to the regime.

In one embodiment, methods for determining the efficacy of a treatmentfor prostate cancer in a subject are provided, such methods comprising:(a) detecting levels of expression of a plurality of biomarkers inbiological samples obtained from the subject at different time intervalsprior to and following administration of the treatment, wherein theplurality of polypeptide biomarkers comprises prostate specific antigen(PSA) and at least one biomarker selected from the group consisting of:C reactive protein (CRP), chromogranin A (CHGA), bone alkalinephosphatase (BAP), cysteine-rich secretory protein 3 (CRISP3), ERG, andprostatic acid phosphatase (PAP; also called ACP3; human acidphosphatase 3, prostatic); and (b) determining changes in the levels ofexpression of the plurality of biomarkers following administration ofthe treatment, wherein a decrease in the level of expression of PSA andan increase in the level of expression of at least one biomarkerselected from CRP, CHGA, BAP, CRISP3, PAP and ERG that is sustained fora period of at least one, two or more weeks indicates that the treatmentis effective in treating prostate cancer in the subject. In certainembodiments, such methods comprise determining levels of expression ofPSA plus at least two, three, four, five or six biomarkers selected fromCRP, CHGA, BAP, CRISP3, ERG and PAP.

In another embodiment, the present disclosure provides methods fordetermining the efficacy of a treatment for prostate cancer in asubject, comprising: (a) detecting levels of expression of at least onebiomarker in biological samples obtained from the subject at differenttime intervals prior to and following administration of the treatment,wherein the biomarker is selected from the group consisting of: Creactive protein (CRP), bone alkaline phosphatase (BAP) andcysteine-rich secretory protein 3 (CRISP3); and (b) determining changesin the level of expression of the at least one biomarker followingadministration of the treatment, wherein a rapid increase in the levelof expression of the at least one biomarker that is sustained for aperiod of less than three or four weeks indicates that the treatment isnot effective in treating prostate cancer in the subject. Theseincreases may be extremely rapid, doubling in concentration (ng/ml)within, for example, two hours or more for a serum protein such as CRP,or two days or more for CRISP3. In certain embodiments, such methodscomprise determining levels of expression of at least two or threebiomarkers selected from CRP, BAP and CRISP3.

In a further embodiment, methods for determining the efficacy of atreatment for prostate cancer in a subject are provided that comprise:(a) detecting levels of expression of a plurality of biomarkers inbiological samples obtained from the subject at different time intervalsprior to and following administration of the treatment, wherein theplurality of polypeptide biomarkers comprises chromogranin A (CHGA),cysteine-rich secretory protein 3 (CRISP3), C reactive protein (CRP),prostatic acid phosphatase (PAP), ERG and bone alkaline phosphatase(BAP); and (b) determining changes in the levels of expression of theplurality of biomarkers following administration of the treatment,wherein an increase in the level of expression of at least one of thebiomarkers of less than 5%, 10% or 15% indicates that the treatment isnot effective in treating prostate cancer in the subject.

In yet another embodiment, the present disclosure provides methods fordetermining the efficacy of a treatment for prostate cancer in a subjectthat comprise: (a) detecting levels of expression of a plurality ofbiomarkers in biological samples obtained from the subject at differenttime intervals prior to and following administration of the treatment,wherein the plurality of polypeptide biomarkers comprises cysteine-richsecretory protein 3 (CRISP3) and ERG; and (b) determining changes in thelevels of expression of the plurality of biomarkers followingadministration of the treatment, wherein an increase in expression of atleast one of the biomarkers indicates that the treatment is effective intreating prostate cancer in the subject.

The polypeptide sequences for PSA, CRP, CHGA, BAP, CRISP3, ERG, PAP andKLK2 are provided in SEQ ID NO: 1-20. In certain embodiments, themethods disclosed herein include detecting the level of expression of apolypeptide comprising a sequence of SEQ ID NO: 1-20, or a variantthereof, as defined herein.

In certain embodiments, the methods disclosed herein are employed tomonitor the efficacy of a treatment regime in a subject with metastaticprostate cancer. Biological samples that can be effectively employed inthe disclosed methods include, but are not limited to, urine, blood andblood products (such as peripheral mononuclear cells (PBMCs)) and serum.

In certain embodiments, the expression levels of the polypeptidebiomarkers employed herein are quantified by immunoassay, such asenzyme-linked immunoassay (ELISA) technology. In specific embodiments,the levels of expression of the polypeptide biomarkers are determined bycontacting the biological sample with antibodies, or antigen bindingfragments thereof, that selectively bind to the polypeptide biomarkers;and detecting binding of the antibodies, or antigen binding fragmentsthereof, to the polypeptide biomarkers. The binding agents employed inthe disclosed methods and compositions are preferably labeled with adetectable moiety.

For example, the level of a polypeptide biomarker in a sample can beassayed by contacting the biological sample with an antibody, or antigenbinding fragment thereof, that selectively binds to the target biomarker(referred to as a capture molecule or antibody), and detecting thebinding of the antibody, or antigen-binding fragment thereof, to thepolypeptide biomarker. The detection is generally performed using asecond antibody to bind to the capture antibody complexed with itstarget biomarker. A target biomarker can be an entire protein, or avariant or modified form thereof. ELISA kits for the detection ofbiomarkers as described herein are commercially available and includepre-coated strip plates, biotinylated secondary antibody, standards,controls (where applicable), buffers, streptavidin-horse radishperoxidase (HRP), tetramethyl benzidine (TMB), stop reagents, anddetailed instructions for carrying out the tests including performingstandards.

In other embodiments, the levels of expression of the biomarkers aredetermined by quantitative real-time polymerase chain reaction.

The present disclosure also provides methods for the detection ofprostate cancer in a subject wherein the levels of expression of thepolypeptide biomarkers in a biological sample are determinedsimultaneously.

In a further aspect, the present disclosure provides compositions thatcan be employed in the disclosed methods. In certain embodiments, suchcompositions a solid substrate and a plurality of binding agentsimmobilized on the substrate, wherein each of the binding agents isimmobilized at a different, indexable or predetermined, location on thesubstrate and the binding agents selectively bind to a plurality ofpolypeptide biomarkers disclosed herein. In certain embodiments, thebinding agents selectively bind to a plurality of polypeptide biomarkerscomprising PSA, CRP, CHGA, BAP, CRISP3, ERG and PAP. Binding agents thatcan be employed in such compositions include, but are not limited to,antibodies, or antigen-binding fragments thereof. Preferably the bindingagents are labeled with a detectable moiety.

In related embodiments, the present disclosure provides compositionscomprising a solid substrate and a plurality of oligonucleotidesimmobilized on the substrate, wherein each of the oligonucleotides isimmobilized at a different, indexable or predetermined, location on thesubstrate and the oligonucleotides are specific for a plurality ofpolynucleotide biomarkers comprising PSA, CRP, CHGA, BAP, CRISP3, ERGand PAP.

Compositions comprising a solid substrate and a plurality of polypeptidebiomarkers immobilized on the substrate are also provided, wherein eachof the polypeptide biomarkers is immobilized at a different, indexableor predetermined, location on the substrate and wherein the plurality ofpolypeptide biomarkers comprises PSA, CRP, CHGA, BAP, CRISP3, ERG andPAP.

In related aspects, the disclosed methods for determining the efficacyof a treatment for prostate cancer in a subject comprise: (a) contactinga first biological sample obtained from the subject prior toadministration of the treatment with a composition disclosed herein; (b)contacting a plurality of subsequent biological samples obtained fromthe subject at a plurality of different, subsequent, time intervalsfollowing administration of the treatment with a plurality ofcompositions disclosed herein; and (c) determining changes in the levelsof expression of the plurality of biomarkers following administration ofthe treatment. In such methods, a decrease in the level of expression ofPSA and an increase in the level of expression of at least one biomarkerselected from CRP, CHGA, CRISP3, ERG, BAP, and PAP that is sustained fora period of at least one or two weeks indicates that the treatment iseffective in treating prostate cancer in the subject; a rapid increasein the level of expression of at least one biomarker selected fromCRISP3, CRP and PAP that is sustained for a period of less than fourweeks indicates that the treatment is not effective in treating prostatecancer in the subject; and an increase in the level of expression of atleast one biomarker selected from CHGA, CRISP3, CRP, PAP, ERG, and BAPof less than 5%, 10% or 15% indicates that the treatment is noteffective in treating prostate cancer in the subject.

In yet another aspect, the present disclosure provides compositionscomprising a solid substrate and a plurality of polypeptide biomarkersdisclosed herein immobilized on the substrate, wherein each of thepolypeptide biomarkers is immobilized at a different, indexable orpredetermined, location on the substrate. In certain embodiments, theplurality of polypeptide biomarkers includes PSA, CRP, CHGA, BAP,CRISP3, ERG and PAP. Such compositions can be employed to monitor theefficacy of a treatment for prostate cancer in a subject by contactingbiological samples obtained from the subject before the start oftreatment and at intervals during treatment with the compositions, anddetermining changes in the levels of autoantibodies against thepolypeptide biomarkers during the treatment regime.

In another aspect, kits for determining the efficacy of a treatment forprostate cancer in a subject are provided, such kits comprising bindingagents that specifically bind to the polypeptide biomarkers disclosedherein and instructions for their use.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A-D depict typical standard curves for A) PSA, B) CRP, C) CHGAand D) CRISP3 for quantification of enzyme linked immunoassays.

FIG. 2 depicts Patient 1 PSA levels prior to and following combinedtreatment with ketoconazole and Leukine®. The arrow depicts the time ofthe start of treatment.

FIG. 3 depicts Patient 2 PSA levels prior to and following combinedtreatment with ketoconazole and Leukine®. The arrow depicts the time ofthe start of treatment.

FIGS. 4A and 4B depict changes in serum levels of CRISP3 in two patientswith metastatic prostate cancer (referred to as Patient 1 and Patient 2,respectively) prior to and during treatment with ketoconazole andLeukine®.

FIGS. 5A and 5B depict CRP and PSA levels in A) Patient 1, and B)Patient 2 prior to and following combined treatment with ketoconazoleand Leukine®.

FIGS. 6A and 6B depict CHGA and PSA levels in A) Patient 1 and B)Patient 2 prior to and following combined treatment with ketoconazoleand Leukine®. The arrows depict the time of the start of treatment.

FIGS. 7A and 7B depict changes in serum levels of PAP and BAP (referredto as ACP3) in Patients 1 and 2, respectively, prior to and followingcombined treatment with ketoconazole and Leukine®.

FIG. 8 depicts changes in CRISP3 and CRP serum levels in Patient 1during treatment with Docetaxel, dexamethasone and prednisolone.

FIG. 9 depicts changes in PAP (referred to as ACP3) and BAP serum levelsin Patient 1 during treatment with Docetaxel, dexamethasone andprednisolone.

FIG. 10 depicts CRISP3 mRNA expression in PBMCs from normal and prostatecancer subjects at multiple time points.

FIG. 11 depicts a summary of increases in CRISP3 mRNA expression inprostate cancer subjects over time.

FIG. 12 depicts ERG mRNA expression in PBMCs from normal (Normal) andprostate cancer (CaP) subjects.

FIG. 13 depicts ERG mRNA expression in PBMCs from normal and prostatecancer subjects at various times.

FIG. 14 depicts a summary of increases in ERG mRNA expression in PBMCsfrom normal and prostate cancer subjects over time.

DEFINITIONS

As used herein, the term “biomarker” refers to a molecule that isassociated either quantitatively or qualitatively with a biologicalchange. Examples of biomarkers include: polypeptides, proteins orfragments of a polypeptide or protein; polynucleotides, such as a geneproduct, RNA or RNA fragment; and other body metabolites.

As used herein, the term “antigen” refers to a synthetic peptide,polypeptide, protein or fragment of a polypeptide or protein, or othermolecule which elicits an antibody response in a subject, or isrecognized and bound by an antibody.

As used herein, the terms “specific binding” or “specifically binding”when used in reference to the interaction of an antibody and a proteinor peptide means that the interaction is dependent upon the presence ofa particular structure (i.e., the epitope) on the protein.

As used herein, the terms “binding agent specific for” or “binding agentthat specifically binds” refers to an agent that binds to a polypeptidebiomarker and does not significantly bind to unrelated proteins.Examples of binding agents that can be effectively employed in thedisclosed methods include, but are not limited to, proteins andantibodies, such as monoclonal or polyclonal antibodies, orantigen-binding fragments thereof. In certain embodiments, the bindingagent binds the polypeptide biomarker with an affinity constant of, forexample, greater than or equal to about 1×10⁻⁶ M.

As used herein, the term “subject” refers to a mammal, preferably ahuman, who may or may not have prostate cancer. Typically, the terms“subject” and “patient” are used interchangeably herein in reference toa human subject.

As used herein, the term “healthy male” refers to a male who has a PSAlevel in serum of less than 1.0 ng/ml, no evidence of prostate glandabnormality following a DRE and no clinical symptoms of prostaticdisorders. Subjects who have no evidence of disease outside the prostategland but whose PSA is climbing are termed “rising PSA” and subjects whoare receiving no further treatments are described as being on “watchfulwaiting”.

As used herein, the term “asymptomatic male” refers to a male who has aPSA level in serum of greater than 8 ng/ml, which is consideredindicative of prostate cancer, but whose DRE is inconclusive and who hasno symptoms of clinical disease.

The term “benign prostate hypertrophy” (BPH) refers to a prostaticdisease with a non-malignant growth of epithelial cells in the prostategland and the term “prostatitis” refers to another prostatic disease ofthe prostate, usually due to a microbial infection of the prostategland. Both BPH and prostatitis can result in increased PSA levels.

As used herein, the term “metastatic prostate cancer” refers to prostatecancer which has spread beyond the prostate gland to a distant site,such as lymph nodes or bone.

As used herein, the term “biopsy tissue” refers to a sample of tissue(e.g., prostate tissue) that is removed from a subject for the purposeof determining if the sample contains cancerous tissue. The biopsytissue is then examined (e.g., by microscopy) for the presence orabsence of cancer.

As used herein, the term “sample” is used refers to a sample, specimenor culture obtained from any source. Biological samples include bloodproducts (such as plasma, serum, whole blood and peripheral bloodmononuclear cells (PBMCs)), urine, saliva and the like. Biologicalsamples also include tissue samples, such as biopsy tissues orpathological tissues, that have previously been fixed (e.g., formalin,snap frozen, cytological processing, etc.).

As used herein, the term “2̂ddCt (delta delta Ct, log scale, base 2)”refers to a method for determining expression levels of genes based onthe Ct value, the threshold number of cycles of amplification via thepolymerase chain reaction (PCR) until the gene is detected usingquantitative or real time PCR. Delta Ct is the difference in Ct betweenthe gene of interest and a control, and ddCt is the difference betweenthe dCt of a gene in an test sample and the dCt of the control in thetest sample compared to the reference sample, (see for example Zhang etal., 2010, “ddCt Method for qRT-PCR Data Analysis”, available on theBioConductor website).

As used herein, the term “predetermined threshold value of expression”of a biomarker refers to the level of expression of the same biomarkerin a corresponding control/normal sample or group of control/normalsamples obtained from normal, or healthy, males, i.e. males who do nothave prostate cancer.

As used herein, the term “altered level of expression” of a biomarker ina test biological sample refers to a level that is either below or abovethe predetermined threshold value of expression for the same biomarkerand thus encompasses either high (increased) or low (decreased)expression levels.

As used herein, the term “oligonucleotide specific for a biomarker”refers to an oligonucleotide that specifically hybridizes to apolynucleotide biomarker or a polynucleotide encoding a polypeptidebiomarker disclosed herein, and that does not significantly hybridize tounrelated polynucleotides. In certain embodiments, the oligonucleotidehybridizes to the polynucleotide of interest under stringent conditions,such as, but not limited to, prewashing in a solution of 6×SSC, 0.2%SDS; hybridizing at 65° C., 6×SSC, 0.2% SDS overnight; followed by twowashes of 30 minutes each in 1×SSC, 0.1% SDS at 65° C. and two washes of30 minutes each in 0.2×SSC, 0.1% SDS at 65° C.

As used, herein the term “polynucleotide(s),” refers to a single ordouble-stranded polymer of deoxyribonucleotide or ribonucleotide basesand includes DNA and corresponding RNA molecules, including HnRNA andmRNA molecules, both sense and anti-sense strands, and comprehends cDNA,genomic DNA and recombinant DNA, as well as wholly or partiallysynthesized polynucleotides. An HnRNA molecule contains introns andcorresponds to a DNA molecule in a generally one-to-one manner. An mRNAmolecule corresponds to an HnRNA and DNA molecule from which the intronshave been excised.

The term “prognosis” or “providing a prognosis” refers to providinginformation regarding the likely impact of the presence of prostatecancer (e.g., as determined by the diagnostic methods) on a subject'sfuture health (e.g., the risk of metastasis).

DETAILED DESCRIPTION

As outlined above, the present disclosure provides methods formonitoring treatment of prostate cancer and/or determining the efficacyof a treatment for prostate cancer in a subject by determining thelevels of specific combinations of biomarkers in biological samplesobtained from the subject both prior to, and during the course of,treatment.

The disclosed methods employ biomarkers selected from those shown inTable 1 below.

TABLE 1 Protein and Gene Expression Biomarkers for Monitoring Treatmentof Prostate Cancer SEQ ID NO: BIOMARKER COMMENTS (AMINO ACID) Prostatespecific antigen Provides PSA levels in serum 1-4 (PSA), also known askallikrein 3 (KLK3) Chromogranin A (CHGA; Detects prostate cancer ofneuroendocrine 5 also referred to as CGA) origin; possessescalcium-binding abilities. C reactive protein (CRP) Correlates withstrong inflammatory 6 response; high levels have been associated withshorter survival and a lower probability of response to chemotherapy.Cysteine-rich secretory Androgen regulated; involved in sperm 7-9protein 3 (CRISP3) maturation Erg Oncogene 10-16 Bone alkalinephosphatase Metastatic bone cancer. 17  (BAP) There are 4 genes in theALP gene family: intestinal, placental, germ cell and non- tissuespecific. The tissue non-specific isoenzyme includes the common serumforms of ALP from bone and liver. Liver and bone ALP are isoforms of thetissue non-specific isoenzyme, differing due to post-translationalglycation. Kallikrein-2 (KLK2) Serine protease with trypsin-like 18 & 19substrate specificity. Splits pro-PSA to create PSA; regulates KLK3production. KLK2 and KLK3 are two of the most highly expressed genes inthe prostate Prostatic acid phosphatase Phosphatase activity inprostate. Increased 20  (PAP) amounts in men who have prostate cancer.

The disclosed methods can be employed to determine the efficacy oftreatments for prostate cancer in subjects who are undergoing androgenablation therapy and/or in subjects who are undergoing chemotherapyincluding, but not limited to, subjects with metastatic prostate cancer

In certain embodiments, panels of isolated prostate cancer polypeptidebiomarkers are provided that include a plurality of polypeptidesequences (for example at least two, three, four, five or six sequences)selected from SEQ ID NO: 1-20. Panels of nucleic acid molecules thatencode the polypeptide biomarkers disclosed herein are also provided,such panels comprising a plurality of polynucleotide sequences (forexample at least two, three, four, five or six sequences) that encodethe polypeptide sequences of SEQ ID NO: 1-20. In related embodiments,panels of binding agents, such as antibodies or antibody fragments, thatare specific for the disclosed polypeptide biomarkers are provided,together with panels of oligonucleotides that specifically hybridize tonucleic acid molecules that encode the disclosed polypeptide biomarkers,or that specifically hybridize to the disclosed polynucleotidebiomarkers.

All of the biomarkers and binding agents disclosed herein are isolatedand purified, as those terms are commonly used in the art. Preferably,the biomarkers and binding agents are at least about 80% pure, morepreferably at least about 90% pure, and most preferably at least about99% pure.

In certain embodiments, the binding agents and/or oligonucleotidesemployed in the disclosed methods specifically bind to a variant of apolypeptide biomarker or polynucleotide biomarker disclosed herein. Asused herein, the term “variant” comprehends nucleotide or amino acidsequences different from the specifically identified sequences, whereinone or more nucleotides or amino acid residues is deleted, substituted,or added. Variants may be naturally occurring allelic variants, ornon-naturally occurring variants. Variant sequences (polynucleotide orpolypeptide) preferably exhibit at least 80%, 85%, 90%, 95%, 96%, 97%,98% or 99% identity to a sequence disclosed herein. The percentageidentity is determined by aligning the two sequences to be compared asdescribed below, determining the number of identical residues in thealigned portion, dividing that number by the total number of residues inthe inventive (queried) sequence, and multiplying the result by 100.

In addition to exhibiting the recited level of sequence identity,variants of the disclosed polypeptide biomarkers are preferablythemselves expressed in subjects with prostate cancer at levels that arehigher or lower than the levels of expression in normal, healthyindividuals.

Variant sequences generally differ from the specifically identifiedsequence only by conservative substitutions, deletions or modifications.As used herein, a “conservative substitution” is one in which an aminoacid is substituted for another amino acid that has similar properties,such that one skilled in the art of peptide chemistry would expect thesecondary structure and hydropathic nature of the polypeptide to besubstantially unchanged. In general, the following groups of amino acidsrepresent conservative changes: (1) ala, pro, gly, glu, asp, gln, asn,ser, thr; (2) cys, ser, tyr, thr; (3) val, ile, leu, met, ala, phe; (4)lys, arg, his; and (5) phe, tyr, trp, his. Variants may also, oralternatively, contain other modifications, including the deletion oraddition of amino acids that have minimal influence on the antigenicproperties, secondary structure and hydropathic nature of thepolypeptide. For example, a polypeptide may be conjugated to a signal(or leader) sequence at the N-terminal end of the protein whichco-translationally or post-translationally directs transfer of theprotein. The polypeptide may also be conjugated to a linker or othersequence for ease of synthesis, purification or identification of thepolypeptide (e.g., poly-His), or to enhance binding of the polypeptideto a solid support. For example, a polypeptide may be conjugated to animmunoglobulin Fc region.

Polypeptide and polynucleotide sequences may be aligned, and percentagesof identical amino acids or nucleotides in a specified region may bedetermined against another polypeptide or polynucleotide sequence, usingcomputer algorithms that are publicly available. The percentage identityof a polynucleotide or polypeptide sequence is determined by aligningpolynucleotide and polypeptide sequences using appropriate algorithms,such as BLASTN or BLASTP, respectively, set to default parameters;identifying the number of identical nucleic or amino acids over thealigned portions; dividing the number of identical nucleic or aminoacids by the total number of nucleic or amino acids of thepolynucleotide or polypeptide of the present invention; and thenmultiplying by 100 to determine the percentage identity.

Two exemplary algorithms for aligning and identifying the identity ofpolynucleotide sequences are the BLASTN and FASTA algorithms. Thealignment and identity of polypeptide sequences may be examined usingthe BLASTP algorithm. BLASTX and FASTX algorithms compare nucleotidequery sequences translated in all reading frames against polypeptidesequences. The FASTA and FASTX algorithms are described in Pearson andLipman, Proc. Natl. Acad. Sci. USA 85:2444-2448, 1988; and in Pearson,Methods in Enzymol. 183:63-98, 1990. The FASTA software package isavailable from the University of Virginia, Charlottesville, Va.22906-9025. The FASTA algorithm, set to the default parameters describedin the documentation and distributed with the algorithm, may be used inthe determination of polynucleotide variants. The readme files for FASTAand FASTX Version 2.0× that are distributed with the algorithms describethe use of the algorithms and describe the default parameters.

The BLASTN software is available on the NCBI anonymous FTP server and isavailable from the National Center for Biotechnology Information (NCBI),National Library of Medicine, Building 38A, Room 8N805, Bethesda, Md.20894. The BLASTN algorithm Version 2.0.6 [Sep. 10, 1998] and Version2.0.11 [Jan. 20, 2000] set to the default parameters described in thedocumentation and distributed with the algorithm, is preferred for usein the determination of variants according to the present invention. Theuse of the BLAST family of algorithms, including BLASTN, is described atNCBI's website and in the publication of Altschul, et al., “Gapped BLASTand PSI-BLAST: a new generation of protein database search programs,”Nucleic Acids Res. 25:3389-3402, 1997.

In an alternative embodiment, variant polypeptides are encoded bypolynucleotide sequences that hybridize to a disclosed polynucleotideunder stringent conditions. Stringent hybridization conditions fordetermining complementarity include salt conditions of less than about 1M, more usually less than about 500 mM, and preferably less than about200 mM. Hybridization temperatures can be as low as 5° C., but aregenerally greater than about 22° C., more preferably greater than about30° C., and most preferably greater than about 37° C. Longer DNAfragments may require higher hybridization temperatures for specifichybridization. Since the stringency of hybridization may be affected byother factors such as probe composition, presence of organic solventsand extent of base mismatching, the combination of parameters is moreimportant than the absolute measure of any one alone. An example of“stringent conditions” is prewashing in a solution of 6×SSC, 0.2% SDS;hybridizing at 65° C., 6×SSC, 0.2% SDS overnight; followed by two washesof 30 minutes each in 1×SSC, 0.1% SDS at 65° C. and two washes of 30minutes each in 0.2×SSC, 0.1% SDS at 65° C.

An “antigen-binding fragment” of an antibody refers to the part of theantibody that participates in antigen binding. The antigen binding siteis formed by amino acid residues of the N-terminal variable (“V”)regions of the heavy (“H”) and light (“L”) chains.

Antibodies may be prepared by any of a variety of techniques known tothose of ordinary skill in the art (see, for example, Harlow and Lane,Antibodies: A Laboratory Manual, Cold Spring Harbor Laboratory, 1988).In general, antibodies can be produced by cell culture techniques,including the generation of monoclonal antibodies as described herein,or via transfection of antibody genes into suitable bacterial ormammalian cell hosts, in order to allow for the production ofrecombinant antibodies.

Monoclonal antibodies may be prepared using hybridoma methods, such asthe technique of Kohler and Milstein (Eur. J. Immunol. 6:511-519, 1976),and improvements thereto. These methods involve the preparation ofimmortal cell lines capable of producing antibodies having the desiredspecificity. Monoclonal antibodies may also be made by recombinant DNAmethods, such as those described in U.S. Pat. No. 4,816,567. DNAencoding antibodies employed in the disclosed methods may be isolatedand sequenced using conventional procedures. Recombinant antibodies,antibody fragments, and/or fusions thereof, can be expressed in vitro orin prokaryotic cells (e.g. bacteria) or eukaryotic cells (e.g. yeast,insect or mammalian cells) and further purified as necessary using wellknown methods.

Antibodies may also be derived from a recombinant antibody library thatis based on amino acid sequences that have been designed in silico andencoded by polynucleotides that are synthetically generated. Methods fordesigning and obtaining in silico-created sequences are known in the art(Knappik et al., J. Mol. Biol. 296:254:57-86, 2000; Krebs et al., J.Immunol. Methods 254:67-84, 2001; U.S. Pat. No. 6,300,064).

Digestion of antibodies to produce antigen-binding fragments thereof canbe performed using techniques well known in the art. For example, theproteolytic enzyme papain preferentially cleaves IgG molecules to yieldseveral fragments, two of which (the “F(ab)” fragments) each comprise acovalent heterodimer that includes an intact antigen-binding site. Theenzyme pepsin is able to cleave IgG molecules to provide severalfragments, including the “F(ab′)₂” fragment, which comprises bothantigen-binding sites. “Fv” fragments can be produced by preferentialproteolytic cleavage of an IgM, IgG or IgA immunoglobulin molecule, butare more commonly derived using recombinant techniques known in the art.The Fv fragment includes a non-covalent V_(H)::V_(L) heterodimerincluding an antigen-binding site which retains much of the antigenrecognition and binding capabilities of the native antibody molecule(Inbar et al., Proc. Natl. Acad. Sci. USA 69:2659-2662 (1972); Hochmanet al., Biochem. 15:2706-2710 (1976); and Ehrlich et al., Biochem.19:4091-4096 (1980)).

Antibody fragments that specifically bind to the polypeptide biomarkersdisclosed herein can also be isolated from a library of scFvs usingknown techniques, such as those described in U.S. Pat. No. 5,885,793.

A wide variety of expression systems are available in the art for theproduction of antibody fragments, including Fab fragments, scFv, V_(L)and V_(H)S. For example, expression systems of both prokaryotic andeukaryotic origin may be used for the large-scale production of antibodyfragments. Particularly advantageous are expression systems that permitthe secretion of large amounts of antibody fragments into the culturemedium. Eukaryotic expression systems for large-scale production ofantibody fragments and antibody fusion proteins have been described thatare based on mammalian cells, insect cells, plants, transgenic animals,and lower eukaryotes. For example, the cost-effective, large-scaleproduction of antibody fragments can be achieved in yeast fermentationsystems. Large-scale fermentation of these organisms is well known inthe art and is currently used for bulk production of several recombinantproteins.

Antibodies that bind to the polypeptide biomarkers employed in thepresent methods, together with ELISA kits that employ such antibodiesfor the detection of the biomarkers employed herein, are well known tothose of skill in the art and are available commercially.

In certain embodiments, the expression level of one or more polypeptidebiomarkers disclosed herein is determined using a binding agent, such asa protein, antibody or antibody fragment, that specifically binds to thebiomarker of interest, for example in an enzyme-linked immunosorbentassay (ELISA), radioimmunoassay, antibody array, Western blot,immunohistochemical, immunoprecipitation or immunofluoresence assay.Methods for performing such assays are well known to those of skill inthe art.

In one ELISA method, a first, or capture, binding agent, such as anantibody that specifically binds the biomarker of interest, isimmobilized on a suitable solid phase substrate or carrier. The testbiological sample is then contacted with the capture antibody andincubated for a desired period of time. After washing to remove unboundmaterial, a second, detection, antibody that binds to a different,non-overlapping, epitope on the biomarker is then used to detect bindingof the polypeptide biomarker to the capture antibody. The detectionantibody is preferably conjugated, either directly or indirectly, to adetectable moiety. Examples of detectable moieties that can be employedin such methods include, but are not limited to, cheminescent andluminescent agents; fluorophores such as fluorescein, rhodamine andeosin; radioisotopes; colorimetric agents; and enzyme-substrate labels,such as biotin.

In another embodiment, the ELISA is a competitive binding assay, whereinlabeled biomarker is used in place of the labeled detection antibody,and the labeled biomarker and any unlabeled biomarker present in thetest sample compete for binding to the capture antibody. The amount ofbiomarker bound to the capture antibody can be determined based on theproportion of labeled biomarker detected.

Solid phase substrates, or carriers, that can be effectively employed insuch assays are well known to those of skill in the art and include, forexample, 96 well microtiter plates, glass, paper, and microporousmembranes constructed, for example, of nitrocellulose, nylon,polyvinylidene difluoride, polyester, cellulose acetate, mixed celluloseesters and polycarbonate. Suitable microporous membranes include, forexample, those described in US Patent Application Publication no. US2010/0093557 A1. Methods for the automation of immunoassays are wellknown in the art and include, for example, those described in U.S. Pat.Nos. 5,885,530, 4,981,785, 6,159,750 and 5,358,691.

The presence of several different biomarkers in a test sample can bedetected simultaneously using a multiplex assay, such as a multiplexELISA. Multiplex assays offers the advantages of high throughput, asmall volume of sample being required, and the ability to detectdifferent proteins across a board dynamic range of concentrations.

In certain embodiments, such methods employ an array, wherein multiplebinding agents (for example capture antibodies) specific for multiplebiomarkers are immobilized on a substrate, such as a membrane, with eachcapture antibody being positioned at a specific, pre-determined,location on the substrate. Methods for performing assays employing sucharrays include those described, for example, in US Patent ApplicationPublication nos. US 2010-0093557A1 and US 2010-0190656A1, thedisclosures of which are hereby specifically incorporated by reference.

Multiplex arrays in several different formats based on the utilizationof, for example, flow cytometry, chemiluminescence orelectron-chemiluminesence technology, are well known in the art. Flowcytometric multiplex arrays, also known as bead-based multiplex arrays,include the Cytometric Bead Array (CBA) system from BD Biosciences(Bedford, Mass.) and multi-analyte profiling (xMAP®) technology fromLuminex Corp. (Austin, Tex.), both of which employ bead sets which aredistinguishable by flow cytometry. Each bead set is coated with aspecific capture antibody. Fluorescence or streptavidin-labeleddetection antibodies bind to specific capture antibody-biomarkercomplexes formed on the bead set. Multiple biomarkers can be recognizedand measured by differences in the bead sets, with chromogenic orfluorogenic emissions being detected using flow cytometric analysis.

In an alternative format, a multiplex ELISA from Quansys Biosciences(Logan, Utah) coats multiple specific capture antibodies at multiplespots (one antibody at one spot) in the same well on a 96-wellmicrotiter plate. Chemiluminescence technology is then used to detectmultiple biomarkers at the corresponding spots on the plate.

The expression level of one or more polypeptide biomarkers in abiological sample can also be determined by mass spectrometry, inparticular liquid chromatography-mass spectrometry (LC-MS) and gaschromatography-mass spectrometry (GC-MS), using methods well known tothose of skill in the art.

The expression levels of one or more polynucleotide biomarkers in abiological sample can be determined, for example, using one or moreoligonucleotides that are specific for the biomarker. For example, thelevels of mRNA corresponding to a prostate cancer biomarker disclosedherein can be detected using oligonucleotides in Southernhybridizations, in situ hybridizations, and quantitative real-time PCRamplification (qRT-PCR). A plurality of oligonucleotides specific for aplurality of biomarkers can be employed in an array format wherein eacholigonucleotide is immobilized at a pre-determined location on asubstrate, such as nitrocellulose membrane. Methods for performing suchassays are well known to those of skill in the art.

The oligonucleotides employed in such methods are generallysingle-stranded molecules, such as synthetic antisense molecules or cDNAfragments, and are, for example, 6-60 nt, 15-30 or 20-25 nt in length.

Oligonucleotides specific for a polynucleotide that encodes apolypeptide biomarker disclosed herein are prepared using techniqueswell known to those of skill in the art. For example, oligonucleotidescan be designed using known computer algorithms to identifyoligonucleotides of a defined length that are unique to thepolynucleotide, have a GC content within a range suitable forhybridization, and lack predicted secondary structure that may interferewith hybridization. Oligonucleotides can be synthesized using methodswell known to those in the art. For use in array formats, theoligonucleotides may be synthesized directly on the surface of asubstrate. Oligonucleotides specific for the prostate cancer biomarkersdisclosed herein are known in the art and are commercially available.

In certain embodiments, the oligonucleotides are labeled using one ormore detectable moieties. DNA or mRNA isolated from a biological sampleis contacted with the labeled oligonucleotides under conditions thatallow for formation of hybridization complexes, and the amount of labelassociated with the hybridization complexes is measured and compared toa standard value.

In one method, the expression level of one or more prostate cancerbiomarkers disclosed herein is determined by first collecting urine froma subject following DRE or prostate massage via a bicycle or exocycle.RNA is isolated from the urine sample and amplified using knowntechniques, such as those described by Laxman et al. (Neoplasia 2006,8:885-8) and the expression level of mRNA corresponding to the biomarkeris determined by, for example, quantitative PCR or RT-PCR using one ormore oligonucleotides specific for the biomarker of interest.

For tests involving alterations in RNA expression levels, it isessential to ensure adequate standardization. Accordingly, in tests suchas quantitative real time PCR or small scale oligonucleotidemicroarrays, at least one expression standard selected is employed.

The present disclosure further provides diagnostic panels including aplurality of binding agents (for example, antibodies) oroligonucleotides that are specific for a plurality (for example, two,three, four, five or six) of the prostate cancer biomarkers disclosedherein. In certain embodiments, such panels are in the form of arrays,or microarrays, in which the binding agents or oligonucleotides areimmobilized at specific locations on a substrate. The binding agents andoligonucleotides are preferably labeled such that the size and signalintensity of each labeled complex formed between the biomarker and thebinding agent/oligonucleotide are individually distinguishable.Alternatively, diagnostic panels are provided in which the biomarkersdisclosed herein are immobilized at specific locations on a substrate.The biomarkers are preferably labeled such that the size and signalintensity of labeled complexes formed between the biomarkers andauto-antibodies present in a biological sample are individuallydistinguishable. Kits comprising such diagnostic panels and instructionsfor their use are also provided. Such kits can also include othercomponents required to carry out the assay, such as buffers,preservatives, wash solutions, etc.

The following examples are intended to illustrate, but not limit, thisdisclosure.

EXAMPLES Methods for Examples Relating to Protein Biomarkers

Human ethics approval for the studies described herein was obtained fromthe Northern X Regional Ethics Committee of New Zealand. A total of 90blood samples were obtained from subjects who were either volunteerdonor healthy males or prostate cancer patients. The distribution ofdonors with respect to prostate disease status and age is shown in Table2 below.

TABLE 2 Characterization of Blood Donors Donor status Number of DonorsDonor Age Range Healthy males 16 33-72 Prostatitis 1 60 Benign Prostatic1 63 Hyperplasia Asymptomatic 3 62-69 males Cancer confined to 6 60-70prostate gland Prostatectomy 21 55-69 performed between 1 and 2 yearsprior to donating blood sample Metastatic disease 42 62-78

Blood samples obtained from the subjects described above were screenedfor levels of protein biomarkers in serum using commercially availableELISA diagnostic kits purchased from Holzel Diagnostika, Germany. Assayswere performed in 96 well microtiter plates and each plate included therelevant standards supplied by the manufacturer to determine a standardcurve. The linear portion of the standard curve was selected fordetermining scores using linear-log or log-log plots of the standardcurve data. Samples for analyzes were diluted to meet the detectionranges for the ELISAs.

The protein and gene expression biomarkers selected for use in themethods disclosed herein are summarized above in Table 1. Typicalstandard curves for A) PSA, B) CRP, C) CHGA, and D) CRISP3 forquantification of enzyme linked immunoassays are shown in FIG. 1.

Example 1 Levels of Biomarker Expression in Different Stages of ProstateCancer

Included in the donor samples were blood samples from 42 metastaticprostate cancer donors. We analyzed levels of PSA, KLK2, PAP, CRISP3,CRP, CGA and BAP, in each sample and then collated the data. On thebasis of the results we were able to divide the metastatic prostatecancer donors into two groups, referred to as “Metastatic Group A” and“Metastatic Group B” as follows:

(i) Group A were males who had undergone hormone deprivation therapy,were considered hormone resistant and were commencing chemotherapy; and

(ii) Group B were males who had undergone more extensive chemotherapytreatment and were survivors.

Distinct patterns of increased PAP, CRISP3, CRP, CGA and BAP wereobserved in serum from Metastatic Group A donors as compared toMetastatic Group B donors as shown in Table 3 below.

TABLE 3 Comparison of Healthy and Metastatic Group A and B Donor SamplesPSA KLK2 CRISP3 CGA CRP BAP PAP ng/ml ng/ml μg/ml ng/ml μg/ml ng/mlng/ml HEALTHY MALES (N = 24) MEAN 0.67 0.35 2.43 6.68 10.85 40.16 4.78SE 0.09 0.09 0.67 0.99 2.72 10.42 1.32 METASTATIC GROUP A (DONORS N =12) MEAN 268.73 0.13 73.36 23.93 19.14 171.09 11.90 SE 86.86 0.04 16.612.29 3.69 36.86 4.13 METASTATIC GROUP B DONORS (N = 30) MEAN 2.61 0.1939.53 8.56 NT 1.00 47.96 SE 0.93 0.10 8.52 0.88 NT 1.00 12.81 NT = nottested.

These data show that in Metastatic Group A samples mean PSA levels werehigh (268 nn/ml) while mean PAP, CRISP3, CRP, CGA and BAP levels wereall increasing. There was no change in KLK2 levels. By contrast, inMetastatic Group B samples mean PSA levels were approaching normallevels (mean=2.61 ng/ml) while mean CRISP3, CRP, and BAP levels werealso approaching normal. However, PAP levels remained high and there wasno change in KLK2 levels.

Example 2 Monitoring Patterns of Biomarker Expression DuringChemotherapy for Prostate Cancer

The expression levels of various biomarkers in two prostate cancersubjects were followed as described below.

Patient 1

A 66 year old male, diagnosed 6 years previously with metastaticprostate cancer and refractory to androgen deprivation therapy, hadceased all treatment for three months. At that time his serum PSA levelwas 509 ng/ml. The patient commenced treatment with daily injections of0.5 mg Leukine® and administration of 400 mg ketoconazole every eighthours. Blood samples were taken two weeks and one week prior to start oftreatment, and thereafter at three weekly intervals. White cells andserum were harvested from the blood samples and analyzed as describedbelow.

Patient 2

A 62 year old male, diagnosed 4 years previously with metastaticprostate cancer and refractory to androgen deprivation therapy, hadcommenced administration of 200-400 mg ketoconazole every eight hours.At that time his serum PSA level was 1086 ng/ml and rising. The patientthen commenced treatment with daily injections of 0.5 mg Leukine® andadministration of 400 mg ketoconazole every eight hours. Blood sampleswere taken immediately prior to the first injection of 0.5 mg Leukine®and thereafter at two to three weekly intervals. White cells and serumwere harvested from the blood samples and analyzed as described below.

Blood Preparation

Whole blood was collected in green-topped heparin tubes. Blood wastransferred to 50 mL Falcon tubes in a sterile hood, and diluted with anequal volume of sterile, pre-warmed phosphate buffered saline (PBS).Diluted blood was then carefully layered over Ficoll™ (Ficoll-Paque™;Amersham Pharmacia) at up to 30 mL diluted blood over 15 mL Ficoll™, andtubes were centrifuged at 1800 rpm for 15 min with no brake to ensuregentle deceleration.

After centrifugation, cells in the buffy coat layer at the Ficoll™interface were harvested using a sterile disposable pipette and washedinto a large volume of sterile, pre-warmed PBS. Cells were then pelletedby spinning at 1000 rpm for 5 min. Wash supernatant was discarded, cellsresuspended in 10 ml sterile, pre-warmed PBS, and counted. The recoveredcell yield was 1×10⁶ cells/ml of whole blood collected.

Patient Monitoring During Treatment with Leukine® and Ketoconazole

After 4 months of treatment with Leukine® and ketoconazole, the PSAlevels of Patient 1 had decreased from 509 to 9.8 ng/ml. The time courseof changing serum prostate antigen levels in Patient 1 both before andafter treatment with Leukine® and ketoconazole is shown in FIG. 2, withthe arrow showing the start of treatment. By contrast, after treatmentthe PSA levels of Patient 2 had decreased from 1086 to 650 ng/ml andshowed no further decrease (FIG. 3). These patients thus appeared tohave different responder phenotypes to the treatment regime.

To expand upon the differences in biomarker levels seen in serum samplesfrom Group A and Group B metastatic prostate cancer donors, Patients 1and 2 were bled at 2-3 week intervals, and CRISP3, CRP and CHGA levelswere measured.

The data in FIGS. 4A and 4B compares changes in serum levels of CRISP3in Patient 1 and Patient 2, respectively. A distinct difference was seenin CRISP3 levels between these two patients. Specifically, Patient 1exhibited increased CRISP3 levels which were sustained for the course ofthe study and correlated with the significant decrease in PSA levels.Patient 2 exhibited a rapid increase in CRISP3 levels which rapidlydisappeared and, in this case, correlated with a much smaller decreasein PSA levels.

FIGS. 5A and 5B depict CRP and PSA levels in Patient 1 and Patient 2,respectively, following combined treatment with ketoconazole andLeukine®. A distinct difference was seen in CRP levels between these twopatients. Patient 1 exhibited increased CRP levels which were sustainedfor the course of the study, and correlated with the significantdecrease in PSA levels. In contrast, Patient 2 exhibited a rapidincrease in CRP levels which rapidly disappeared and, in this case,correlated with a much smaller decrease in PSA levels.

FIGS. 6A and 6B depict similar trends in CHGA and PSA levels in Patients1 and 2 following combined treatment with ketoconazole and Leukine®.Patient 1 exhibited increased CHGA levels which were sustained for thecourse of the study, and correlated with the significant decrease in PSAlevels. CHGA levels for Patient 2 did not increase above the backgroundsensitivity of the ELISA, which was less than 0.3 ng/ml. Again, thesedata supported the interpretation that these patients appeared to havedifferent responder phenotypes to the treatment regime.

The data in FIGS. 7A and 7B compares changes in serum levels of PAP(referred to in FIGS. 7A and B as ACP3) and BAP in Patients 1 and 2,respectively. Patient 1 exhibited increased PAP and BAP levels whichwere sustained for the course of the study correlated with thesignificant decrease in PSA levels. Patient 2 exhibited an initialincrease in PAP levels then a decrease, similar to the trend inbiomarkers CRP, CHGA and CRISP3.

In summary, the two patients showed different response phenotypes duringtreating with Leukine® and ketoconazole. Specifically, Patient 1exhibited increased CRISP3, CRP, and CHGA levels which were sustainedfor the course of the study and correlated with the significant decreasein PSA levels. In contrast, Patient 2 showed a sharp, transientelevation of CRISP3 and CRP after the start of treatment, while thelevels of CHGA for this patient did not increase above the backgroundsensitivity of the ELISA, and the decrease in PSA levels was small.CRISP3 and CRP both have properties of acute phase proteins, with innateimmune cells producing CRISP3 and adaptive immune cells producing CRP.Inflammatory mediators stimulate the production of CHGA fromneuroendocrine cells, with CHGA being a neuroendocrine biomarker. Onepossible interpretation of these results is that the immune system ofPatient 2 was severely impaired while the immune system of Patient 1 wasmore active.

Patient 1 exhibited increased PAP and bone alkaline phosphatase (BAP)levels which were sustained for the course of the study correlated withthe significant decrease in PSA levels. Patient 2 exhibited an initialincrease in PAP levels then a decrease similar to the trend inbiomarkers CRISP3, CRP and CGA. PAP increases in metastatic cancerduring treatment and is a biomarker for residual prostate cancer cells.BAP is released during bone damage and healing and is indicative thatbone lesions are being destroyed.

Patient Monitoring During Docetaxel Treatment

Following seven months of treatment with ketoconazole and Leukine®treatment, Patient 1 was rested for five weeks and then commencedtreatment with Docetaxel, dexamethasone and prednisolone, following athree week cycle. The patient received six cycles of docetaxel treatmentand then treatment was stopped. Blood samples were taken at the start oftreatment and then at monthly intervals, and the levels of thebiomarkers PAP, CRISP3, CRP and BAP were determined.

The data of FIG. 8 shows that, following start of treatment, an increasein CRISP3 and CRP serum levels for three cycles of chemotherapy wasobserved followed by a decrease. By cycle four, serum levels of bothCRISP3 and CRP had reached background and showed no further increase.The data of FIG. 9 shows that, following start of treatment, there was agradual drift downwards of PAP (referred to in the figure as ACP3) andBAP serum levels and no increase above starting levels was observed.

The decrease in CRISP3 and CRP levels is indicative of the immune system(and perhaps liver) being slowly degraded by continuing chemotherapy andnot recovering in three weeks. This profile indicates that treatmentbeyond four cycles is not beneficial to the patient. There was a gradualdrift downwards of PAP and BAP serum levels that showed no increaseabove starting levels. BAP indicates bone repair is ceasing and thereare reports that PAP levels generally accompany metastatic prostatecancer cells.

Methods for Examples Relating to Gene Expression Biomarkers

Gene expression analyses were performed using PBMCs from a group of 15prostate cancer patients and five healthy subjects (three males and twofemales). The healthy males were determined to be free of prostatecancer and showed no evidence of prostate cancer in a 12 month followup. Blood was collected at different times over a four month period. Thecollection times of specific donor samples are shown in Table 4,together with an internal code, gender and disease status (CaP=prostatecancer; Norm=healthy subject; dates shown as day/month/year).

TABLE 4 Blood collection from healthy (Normal) and prostate cancer (CaP)subjects at different times 12/08/ Code Gender Status 2010 9/09/201021/09/2010 11/10/2010 2/11/2010 9/11/2010 29/11/2010 7/12/2010 4/02/20111 male CaP x x x x x x x 2 male CaP x 3 male Normal x x x x x x x 4 maleNormal x x x 5 male CaP x 6 male CaP x 7 female Normal x 8 female Normalx 9 male CaP x x 10 male CaP x 11 male CaP x x 12 male CaP x 13 male CaPx 14 male CaP x 15 male CaP x 16 male CaP x x x x x x 17 male CaP x 18male CaP x x x x 19 male Normal x 20 male CaP x

PBMCs were purified by centrifugation over a layer of Ficoll™ Hypaqueand RNA extractions using recovered cells were all performed withTRIZOL™ (Invitrogen, Cat#15596-026), according to the manufacturer'sinstructions. cDNA amplifications were performed with SuperScript VILOcDNA Synthesis Kit (Invitrogen, Cat#11754-250) containing (10×)SuperScript Enzyme Mix and (5×) VILO Reaction Mix. Briefly, 10 μl of thesample (10 ng/μl final concentration) was added to a PCR tube strip. Themaster mix was prepared according to the manufacturer's protocol and 10μl of the master mix was added, mixed by vortexing for a few seconds andcentrifuged at 1,000 rpm for a few seconds. Amplification involved thefollowing steps: 10 minutes at 25° C.; 60 minutes at 42° C.; 5 minutesat 85° C.; held at 4° C. Storage of the cDNA was at −20° C.

Quantitative Real Time PCR amplification employed INVITROGEN PLATINUM™SYBR® Green qPCR SuperMix-UDG with ROX (Cat. no. 11744-500). Briefly,cDNA samples retrieved from −20° C. were tested in triplicate. Sampleswere briefly centrifuged, diluted 1:5 with RNase free water, mixed andcentrifuged. 2 μl of each cDNA was transferred to appropriate wells of a384-well microtiter plate. For a single reaction, 5 μl of Syber greenmaster mix plus 0.2 μl of 10 μM forward and reverse specific primersplus were mixed with 2.6 μl of RNase free water. Then 8 μl of eachmaster mix was transferred to appropriate assays in microwells and theplates sealed with optical plastic. After mixing by vortexing, theplates were centrifuged briefly, and then analyzed via qRT-PCR (7900 HTFast Real Time PCR System, Applied Biosystems).

Conditions used for qRT-PCR are described in Table 5, below, and theoligonucleotide primers investigated are depicted in Table 6.

TABLE 5 Conditions used for qRT-PCR Programme Number Dissociation stepNumber 50° C. × 2 min. 1 95° C. × 15 sec. 95° C. × 2 min. 1 60° C. × 15sec. 1 95° C. × 15 sec. 40 95° C. × 15 sec. 60° C. × 1 min.

TABLE 6 Primers Employed Catalog No. Catalog No. qRT (Forward/ qRT(Forward/ Primers Supplier Reverse) Primers Supplier Reverse) CRISP3Invitrogen V4154C05/ PEX10 Invitrogen V4153D01/V V4154C06 4153D02 ERGIDT* 60992473/ SIM2 IDT* 61006528/ 60992474 61006529 *IDT = IntegratedDNA Technologies

Example 3 Monitoring CRISP3 mRNA Expression in Prostate Cancer PatientsDuring Treatment with Ketoconazole and Leukine®

The level of CRISP3 mRNA expression was followed in three prostatecancer subjects (patient 1 (donor code 1), patient 2 (donor code 18) andpatient 3 (donor code 16)) and one healthy male subject. Patients 1 and2 are described above in Example 1.

Patient 3 (Donor Code 16)

A 62 year old male, diagnosed 3 years previously with prostate cancer,had a prostatectomy 6 months after diagnosis and had receivedintermittent androgen deprivation therapy. At the start of the study theprostatectomy had taken place two and a half years previously and hisPSA levels were less than 0.1 ng/ml where they remained for the durationof the study. This patient was not treated during the duration of themonitoring described below.

Healthy Control Subject

Blood samples were taken from a healthy 40 year old male donor with aPSA level of less than 0.1 ng/ml before and through the duration of thestudy.

The expression of CRISP3 mRNA was analyzed in Patient 1 from beforetreatment (12 Aug. 2010), the start of treatment being 5 Sep. 2010; inPatient 2 from 21 Sep. 2010, which was immediately prior to the start ofcombined Leukine®/ketoconazole treatment; and in Patient 3, who was nottreated with any regime, from 12 Aug. 2010.

Blood samples were collected over the period 12 Aug. 2010 to 4 Feb.2011. Quantitative real time PCR analysis of samples collected atdifferent times showed an increase in expression of CRISP3 mRNA inPatients 1 and 2 (donor codes 1 and 18, respectively) but not in Patient3 (donor code 16) over the observed period (see FIG. 10 and Table 7;compare 2̂ddCt values for samples 1 and 18 with 2̂ddCt value of sample16). The samples were normalized on GAPDH and compared with the negativecontrol value of normal donor 03. In Table 7, the 2̂ddCt value of twomore healthy donors 4 and 19 were added to give more backgroundinformation on CRISP3 levels in normal subjects.

TABLE 7 CRISP3 mRNA expression in healthy (normal) and prostate cancer(CaP) subjects CaP Donor CRISP3 mRNA Code Status Date 2{circumflex over( )}-ddCt error bars 1 CaP August 12 15.87 2.73 September 9 323.98 25.57September 21 323.58 25.46 October 11 62.37 12.05 November 2 162.56 21.84December 7 26.09 4.80 February 4 82.87 2.22 16 CaP August 12 15.13 2.16September 9 / / September 21 9.63 2.36 October 11 1.56 0.56 November 2 // December 7 1.90 0.30 February 4 6.48 1.07 18 CaP August 12 / /September 9 / / September 21 143.32 7.01 October 11 442.23 83.33November 2 224.72 44.95 December 7 100.41 6.02 February 4 / / 4 NormalAugust 12 14.73 0.90 September 9 8.03 0.92 19 Normal November 2 8.216.24

A summary of CRISP3 expression from Patients 1 to 3 is shown in FIG. 11where the total increase in expression of CRISP3 for each patient'ssamples collected over the study from 12 Aug. 2010 to 4 Feb. 2011 areshown. The samples were normalized on GAPDH. To summarize, both Patients1 and 2 showed significant increases in CRISP3 RNA expression aftertreatment with ketoconazole and Leukine®, indicating that ketoconazoleand/or Leukine® were involved in stimulating the CRISP3 gene.

Example 4 Monitoring ERG mRNA Expression in Prostate Cancer PatientsTreated with Ketoconazole and Leukine®

ERG gene expression has been reported to be common to many prostatecancers. Quantitative real time PCR analysis for expression of ERG mRNAwas performed on a set of blood samples collected at the same time point(9 Sep. 2010) from a number of prostate cancer subjects and normaldonors. The results showed a unique expression pattern with asignificantly increased level of expression of ERG in Patient 1 (donorcode 1) compared to the other donors collected at the same time point(see FIG. 12 and Table 8, compare sample code 1, 2̂ddCt value14.14+/−2.53 with 2̂ddCt value samples 2 to 14). The samples arenormalized on GAPDH and compared with the negative control value 03(yellow highline).

TABLE 8 ERG mRNA expression in healthy (normal) and prostate cancersubjects. ERG mRNA Expression Normalized on Donor 3 Sep. 09, 2010 CodeStatus 2{circumflex over ( )}-ddCt error bars 1 CaP 14.14 2.53 2 CaP1.16 0.29 3 Normal 1.00 0.17 4 Normal 2.02 0.58 5 CaP 0.92 0.26 6 CaP0.52 0.10 7 Normal 2.07 0.42 8 Normal 0.91 0.07 9 CaP 1.19 0.34 10 CaP1.63 0.59 11 CaP 0.20 0.04 12 CaP 1.45 0.66 13 CaP 1.69 0.32 14 CaP 5.022.73

In order to assess the effect of treatment with ketoconazole andLeukine® on the expression of ERG mRNA in Patients 1, 2 and 3, sampleswere collected as described above from 12 Aug. 2010 to 4 Feb. 20101 andanalyzed by quantitative real time PCR for levels of ERG RNA. Thesamples collected at different times showed a significant increase ofthe mRNA level of ERG in Patients 1 and 2 (donor codes 1 and 18,respectively) compared to no changes in Patient 3 (donor code 16) whoreceived no ketoconazole/Leukine® treatment. The higher ERG expressionof Patient 1 showed a reduction to a baseline expression levels over thecourse of several months, matching with the expression level of Patient2 (see FIG. 13 and Table 9, compare 2̂ddCt value samples 1 and 18 withsample 16), and with the expression level in the healthy donors (Table9, compare 2̂ddCt value samples 1, 18 and 16 with samples 4 and 19). Thesamples were normalized on GAPDH and compared with the negative controlvalue of donor 03. Table 9 includes the relative value of two normaldonors, 4 and 19, to illustrate background ERG mRNA levels.

TABLE 9 ERG mRNA expression in healthy (normal) and prostate cancersubjects CaP Donor ERG mRNA Code Status Date 2{circumflex over ( )}-ddCterror bars 1 CaP August 12 2.52 0.64 September 9 14.14 2.53 September 2112.18 1.09 October 11 17.92 2.20 November 2 5.14 1.15 December 7 2.300.18 February 4 6.51 0.82 16 CaP August 12 2.26 0.92 September 9 / /September 21 2.93 0.55 October 11 4.74 1.43 November 2 / / December 71.40 0.20 February 4 4.01 1.13 18 CaP August 12 / / September 9 / /September 21 16.59 2.42 October 11 81.13 14.07 November 2 10.99 1.00December 7 14.46 0.80 February 4 / / 4 Normal August 12 5.62 0.48September 9 2.02 0.59 19 Normal November 2 1.01 0.77

FIG. 14 shows the relative increase in expression of the ERG mRNAindividually for Patients 1, 2 and 3 over the duration of the study. Allthe data was normalized on the ct value of normal donor 3.

While the present invention has been described with reference to thespecific embodiments thereof, it should be understood by those skilledin the art that various changes may be made and equivalents may besubstituted without departing from the true spirit and scope of theinvention. In addition, many modifications may be made to adapt aparticular situation, material, composition of matter, method, methodstep or steps, for use in practicing the present invention. All suchmodifications are intended to be within the scope of the claims appendedhereto.

All of the publications, patent applications and patents cited in thisapplication are herein incorporated by reference in their entirety tothe same extent as if each individual publication, patent application orpatent was specifically and individually indicated to be incorporated byreference in its entirety.

SEQ ID NO: 1-20 are set out in the attached Sequence Listing. The codesfor nucleotide sequences used in the attached Sequence Listing,including the symbol “n,” conform to WIPO Standard ST.25 (1998),Appendix 2, Table 1.

1. A method for determining the efficacy of a treatment for prostatecancer in a subject, the method comprising: (a) detecting levels ofexpression of a plurality of biomarkers in biological samples obtainedfrom the subject at different time intervals prior to and followingadministration of the treatment, wherein the plurality of polypeptidebiomarkers comprises prostate specific antigen (PSA) and at least onebiomarker selected from the group consisting of: C reactive protein(CRP), chromogranin A (CHGA), bone alkaline phosphatase (BAP),cysteine-rich secretory protein 3 (CRISP3), ERG, and prostatic acidphosphatase (PAP); and (b) determining changes in the levels ofexpression of the plurality of biomarkers following administration ofthe treatment, wherein a decrease in the level of expression of PSA andan increase in the level of expression of at least one biomarkerselected from CRP, CHGA, BAP, CRISP3, ERG and PAP that is sustained fora period of at least two weeks indicates that the treatment is effectivein treating prostate cancer in the subject.
 2. The method of claim 1,wherein the prostate cancer is a metastatic prostate cancer.
 3. Themethod of claim 1, wherein the biological samples are selected from thegroup consisting of: urine, blood and serum.
 4. The method of claim 1,wherein the levels of expression of the plurality of biomarkers aredetermined by immunoassay.
 5. The method of claim 1, wherein step (a)comprises: (a) contacting the biological samples with antibodies, orantigen binding fragments thereof, that selectively bind to thebiomarkers; and (b) detecting the binding of the antibodies, or antigenbinding fragments thereof, to the biomarkers.
 6. A method fordetermining the efficacy of a treatment for prostate cancer in asubject, the method comprising: (a) detecting levels of expression of atleast one biomarker in biological samples obtained from the subject atdifferent time intervals prior to and following administration of thetreatment, wherein the at least one biomarker is selected from the groupconsisting of: C reactive protein (CRP), bone alkaline phosphatase (BAP)and cysteine-rich secretory protein 3 (CRISP3); and (b) determiningchanges in the level of expression of the at least one biomarkerfollowing administration of the treatment, wherein a rapid increase inthe level of expression of the at least one biomarker that is sustainedfor a period of less than four weeks indicates that the treatment is noteffective in treating prostate cancer in the subject.
 7. The method ofclaim 6, wherein the prostate cancer is a metastatic prostate cancer. 8.The method of claim 6, wherein the biological samples are selected fromthe group consisting of: urine, blood and serum.
 9. The method of claim6, wherein step (a) comprises: (a) contacting the biological sampleswith antibodies, or antigen binding fragments thereof, that selectivelybind to the biomarkers; and (b) detecting the binding of the antibodies,or antigen binding fragments thereof, to the biomarkers.
 10. A methodfor determining the efficacy of a treatment for prostate cancer in asubject, the method comprising: (a) detecting levels of expression of aplurality of biomarkers in biological samples obtained from the subjectat different time intervals prior to and following administration of thetreatment, wherein the plurality of polypeptide biomarkers compriseschromogranin A (CHGA), cysteine-rich secretory protein 3 (CRISP3), Creactive protein (CRP), prostatic acid phosphatase (PAP), and bonealkaline phosphatase; and (b) determining changes in the levels ofexpression of the plurality of biomarkers following administration ofthe treatment, wherein an increase in the level of expression of atleast one of the biomarkers of less than 5% indicates that the treatmentis not effective in treating prostate cancer in the subject.
 11. Themethod of claim 10, wherein the prostate cancer is a metastatic prostatecancer.
 12. The method of claim 10, wherein the biological samples areselected from the group consisting of: urine, blood and serum.
 13. Themethod of claim 10, wherein step (a) comprises: (a) contacting thebiological samples with antibodies, or antigen binding fragmentsthereof, that selectively bind to the biomarkers; and (b) detecting thebinding of the antibodies, or antigen binding fragments thereof, to thebiomarkers.
 14. A method for determining the efficacy of a treatment forprostate cancer in a subject, the method comprising: (a) detectinglevels of expression of a plurality of biomarkers in biological samplesobtained from the subject at different time intervals prior to andfollowing administration of the treatment, wherein the plurality ofpolypeptide biomarkers comprises cysteine-rich secretory protein 3(CRISP3) and ERG; and (b) determining changes in the levels ofexpression of the plurality of biomarkers following administration ofthe treatment, wherein an increase in expression of at least one of thebiomarkers indicates that the treatment is effective in treatingprostate cancer in the subject.
 15. The method of claim 14, wherein theprostate cancer is a metastatic prostate cancer.
 16. A compositioncomprising a solid substrate and a plurality of binding agentsimmobilized on the substrate, wherein each of the binding agents isimmobilized at a different, indexable, location on the substrate and thebinding agents selectively bind to a plurality of polypeptidebiomarkers, the plurality of polypeptide biomarkers comprising PSA, CRP,CHGA, BAP, CRISP3, ERG and PAP.
 17. A composition comprising a solidsubstrate and a plurality of polypeptide biomarkers immobilized on thesubstrate, wherein each of the polypeptide biomarkers is immobilized ata different, indexable, location on the substrate and wherein theplurality of polypeptide biomarkers comprises PSA, CRP, CHGA, bonealkaline phosphatase, CRISP3, ERG and PAP.
 18. A composition comprisinga solid substrate and a plurality of oligonucleotides immobilized on thesubstrate, wherein each of the oligonucleotides is immobilized at adifferent, indexable, location on the substrate and the oligonucleotidesare specific for a plurality of polynucleotide biomarkers comprisingPSA, CRP, CHGA, bone alkaline phosphatase, CRISP3 and ERG.
 19. A methodfor determining the efficacy of a treatment for prostate cancer in asubject, the method comprising: (a) contacting a first biological sampleobtained from the subject prior to administration of the treatment witha composition of claim 17; (b) contacting a plurality of subsequentbiological samples obtained from the subject at a plurality of differenttime intervals following administration of the treatment with aplurality of compositions of claim 18; and (c) determining changes inthe levels of expression of the plurality of biomarkers followingadministration of the treatment, wherein: (i) a decrease in the level ofexpression of PSA and an increase in the level of expression of at leastone biomarker selected from CRP, CHGA, CRISP3, BAP, ERG and PAP that issustained for a period of at least one week indicates that the treatmentis effective in treating prostate cancer in the subject; (ii) a rapidincrease in the level of expression of at least one biomarker selectedfrom the group consisting of: CRISP3, CRP and PAP that is sustained fora period of less than four weeks indicates that the treatment is noteffective in treating prostate cancer in the subject; and (iii) anincrease in the level of expression of at least one biomarker selectedfrom the group consisting of: CHGA, CRISPS, CRP, PAP and BAP of lessthan 5% indicates that the treatment is not effective in treatingprostate cancer in the subject.
 20. The method of claim 19, wherein thebiological samples are blood samples.